1. Technical Field
The present invention relates to a structure of a semiconductor device, and more particularly to a structure of a semiconductor device provided with a semiconductor circuit or the like which includes a MIS (Metal Insulator Semiconductor) transistor.
2. Background Art
FIG. 9(a) is a view showing one example of a cross-sectional structure of a conventional semiconductor device, and FIG. 9(b) is a view showing one example of a top structure of the conventional semiconductor device.
As shown in FIGS. 9(a) and (b), transistors 5 composing the semiconductor device are formed on wafer-shaped semiconductor substrate 1 formed of Si or GaAs in general. Each of transistors 5 has gate electrode 2 formed above semiconductor substrate 1 with gate insulator film 3 interposed therebetween, and source and drain regions 4 formed on both sides of gate electrode 2, in semiconductor substrate 1. Interlayer insulator film 6 is formed on semiconductor substrate 1 so as to cover an upper part of transistor 5, and electrode pad 7 is provided on interlayer insulator film 6 so as to electrically connecting the semiconductor device including transistor 5 to an external device. In general, electrode pad 7 is formed of Al. In addition, interlayer insulator film 6 is generally covered except for a formation region of electrode pad 7 with a surface protective film having a two-layer structure, that is, first surface protective film 8 formed of SiN or the like, and second surface protective film 9 formed of polyimide or the like.